In recent weeks, Hungary has released 777 foreign nationals, mostly Serbs, Ukrainians and Romanians, convicted of human trafficking, the Hungarian Office of Prisons (BvOP) announced on Wednesday in response to a Reuters request, Agerpres reports.

According to the BvOP, there are 2,636 people convicted of human trafficking in Hungarian prisons, 808 of whom are foreigners eligible for release.

“Imprisonment of foreign citizens costs Hungarian prisons billions of forints every year,” the BvOP press service notes. In his answer, he also stated that if the released persons do not leave the territory of Hungary within 72 hours and are caught by the police, they will be forced to remain in prison until the end of the term.

In April, Hungarian Prime Minister Viktor Orbán issued a decree to release hundreds of foreign nationals convicted of human trafficking, citing prison overcrowding.

The decree conditioned release on leaving the territory of Hungary within 72 hours. The decision sparked protests from neighboring Austria, a priority destination for migrants heading to the heart of the European Union via Hungary from the Balkans.

According to Vienna, the release of these traders poses a security threat. The Hungarian route remains attractive to many migrants despite increased border patrols and a metal fence built by Hungary on its southern border with Serbia after the 2015 EU migration crisis.

Once in Hungary, migrants can cross the generally open borders of the Schengen zone to more prosperous Western countries such as Austria or Germany.

Although the relevant figures have not yet been released, earlier this year the European Commission estimated that Europe would face the largest influx of migrants since 2015 this spring and took measures to secure borders.